Barrel fastening means



June 21, 1938. Q R LALQUX 2,121,171

BARREL FASTENING MEANS Original Filed Aug. 17, 1935 2 Sheets-Sheet l M Op 48 \NVENTOR REN LALOUX ATTORNEY June 21,' 1938; R. LALOUX 2,121,171

BARREL FASTENING MEANS Original Filed Aug. 1'7, 1955 2 Sheets-Sheet 2 I WNVENTOR RENE LALOUX ATTORN 35 extension of the barrel.

Patented June 21, 1938 BARREL FASTENING NEEAN S Rene Laloux, Brussels, Belgium Original application August 17, 1935, Serial No. 36,740. Divided and this application May 1, 1936, Serial No. 77,426. In Belgium August 2 Claims.

' grip for connecting the barrel to the frame of the firearm: in this system the ring with broken threads is mounted on the frame of the firearm and receives the threaded end of the barrel in order to connect it rigidly with the frame of the firearm.

The object of the present invention is to use the grip of the ring with broken threads to transport the barrel, to put it into position on the firearm and to lift it off easily.

The idea of providing a grip serving at the same time for transporting the barrel and for fastening it on the firearm is not new but it is new to arrange the ring with broken threads in such a way that the grip arranged on this ring serves at the same time for the transport and putting into position of the barrel. For

this purpose a ring, on which a grip is arranged, is screwed onto an extension of the barrel containing the chamber and carries an external broken thread engaging into a corresponding inside thread of the breach case of the firearm.

According to the invention the external thread on the ring has a pitch slightly greater than that of the thread between the ring and the This fastening means allows a very strong attachment to be obtained even if the barrels are not strictly identical and it consequently permits relatively large constructional tolerances.

In order to prevent accidental slackening of the barrel, the ring is provided with a springpressed pawl co-operating with stop notches provided on the breech case.

In order to facilitate the removal of the gas piston when dismounting the barrel, the invention provides on the vertical face of the frame situated in front of the ring an abutment operable on at the end of the opening motion of the ring to push the barrel forward.

In order to obtain a good guiding of the barrels when remounting, the frame and the barrel are provided with sliding plane faces serving for facilitating the introduction of the barrel; this frame is also provided with a fork which 5 surrounds the barrel towards the forward part of the gas cylinder, said fork being provided with two fiat sides which cooperate with two lateral fiat sides belonging to the barrel.

The annexed drawings show by way of example and in a non limiting manner an embodiment of the invention.

Fig. 1 is an exterior view of a machine gun provided with a barrel fastening means according to the invention.

Fig. 2 is an enlarged view of a part of Fig. 1 in partial section.

Fig. 3 is an enlarged plan view of a part of Fig. 1.

Fig. 4 is a rear view of the barrel.

Fig. 5 is a front view of the breech case.

The barrel i8 is provided at its rear part with an extension la in which the chamber 53 is provided. This barrel extension [8a is engaged with sliding-friction into the forepart of the breech box 23 and is provided with a screw thread 3i on which is threadedly mounted a ring 35 provided with an external interrupted screw thread 36 comprising two parts which are diametrally opposed.

In the forepart of the breech box is provided an internal screw thread 31 which corresponds to the thread 36; and besides, apertures 38 diametrally opposed are provided in order to allow the introduction of the screw threaded parts 36 of the ring 35.

In order to fix the barrel it is necessary after longitudinal insertion of the screw 36 into the apertures 38, to rotate the ring 35 about a quarter of a turn around its axis in order to engage the screw thread 36 into the screw thread 31 of the breech box.

The pitch of this external screw thread 3'6 of the ring is slightly greater than that of the inside screw thread 34 and consequently by rotating the ring 35 the bearing face 39 of the barrel is strongly pressed against the corresponding face of the forepart of the breech box.

As shown in the drawings, the ring 35 is connected to a handle it! by means of a rod 45 along which slides a spring-pressed pawl 4|. This handle serves for rotating the ring and for the carriage either of the barrel alone or the automatic rapid fire gun with its barrel.

The pawl 41 has an abutment 42 cooperating with ratchet notches or grooves 43 provided in the lateral outside face of the breech box. These grooves avoid the accidental unlocking of the ring whatever the final position of the abutment 42 of the pawl 4| may be.

A groove 44 is provided upon the forepart of the breech box in such a place that when the abutment 42 is in register with this groove the outside screw thread 36 of the ring is disengaged from the inside screw thread. 3'1 of the breech box, that is to say the barrel is ready for lateral disconnection.

In order to remove the gas piston 4 when dismounting the barrel, a small inclined abutment 46 is provided on the forepart of the breech box and the rod along which slides the pawl 4! presses against this abutment to produce the for- Ward motion of the barrel.

For facilitating the introduction of the barrel when remounting the arm a double guide is provided comprising lateral fiat sides 41 on the forepart of the barrel. These flat sides frictionally cooperate with a fork 43 provided near the end of the gas cylinder to ensure a correct positioning of the barrel when setting it in place in the breech.

In order to obtain a correct regulation in height of the barrel, a sliding plane face 49 is provided towards the forepart of the gas cylinder and cooperates with a corresponding plane face of the barrel; besides, towards the rear part of the barrel is provided another plane face 50 which slides on the upper end of the ribs 5| which are provided towards the rear part of the gas cylinder.

The invention is not limited to the embodiment described by way of example, but includes all machine guns or like firearms which enter within the scope of one or the other of the following claims.

What I claim is:

1. A machine gun or similar firearm comprising a barrel provided with an extension at the breech end thereof, a breech casing provided with a socket to receive said extension, said socket having a portion of larger diameter than said barrel extension provided with broken internal screw threads, the external surface of said barrel extension having continuous screw threads formed thereon, a ring threadedly mounted on said barrel extension, said ring having broken threads on the exterior thereof adapted to cooperate with the broken threads in said socket to permit axial insertion of the ring in said socket and to retain the ring therein upon relative rotary movement between the ring and socket, a carrying and actuating handle on said ring, the exterior surface of said breech casing having a series of notches formed thereon, and a pawl mounted. on said handle and adapted to engage one of said notches on the exterior of the breech casing to secure the ring in adjusted rotary positions.

2. A machine gun or similar firearm comprising a barrel provided with an extension at the breech end thereof, a breech casing provided with a socket to receive said extension, said socket having a portion of larger diameter than said barrel extension provided with broken internal screw threads, the external surface of said barrel extension having continuous screw threads formed thereon, a ring threadedly mounted on said barrel extension, said ring having broken threads on theexterior thereof adapted to cooperate with the broken threads in said socket to permit axial insertion of the ring in said socket and to retain the ring therein upon relative rotary movement between the ring and socket, the broken threads of the ring and socket being of a pitch greater than that of the continuous thread of the barrel extension and ring, a carrying and actuating handle on said ring, the exterior surface of said breech casing having a series of notches formed thereon, and a pawl mounted on said handle and adapted to engage one of said notches on the exterior of the breech casing to secure the ring in adjusted rotary positions.

RENE LALOUX. 

